Gents

Could the 707 perform a full auto landing already in 1960/70 ?
The CS707 is doing ILS landing in perfect style but since when was that possilbe with the 707 . I know the HS 1 Trident was the first Jet to do autolandings.

Jan Koppen

The short answer - NO! 

The lowest you could go with the autopilot connected was 50 feet. The 707 and 727 did not have autoland, there were some mods that were added to the 727 in its later life, but that was like putting the brain of a 16 year old in the body of a 80 year old. Even the early 747's had to be landed by hand. The first U.S. production airliner I can recall that had true autoland was the L-1011. It was way ahead of its time. The L-1011 had something called DLC (direct lift control). During the approach in order to make the aircraft more stable the G/S, which in a normal plane was tracked by pitch, in the L-1011 used a special system called DLC. The spoilers would float and adjust the rate of descent to hold the G/S. The advantage was a constant deck angle which kept the power changes to a minimum thus a more stable approach.

When the 767, 757 group came out, then Boeing had developed a true autoland system. The 707, 727, 747 all had the same problem. Their wings had to be kept level during touchdown or either an engine or leading edge would contact the runway. This meant that the landing had to be done in a crab if there was a crosswind. This was a real problem for the 747 on a 150 foot wide runway since if you had the cockpit on the center line the main landing gear could be off the runway. It was one thing for the pilot to kick the rudder at the last minute and align the plane and something else for the autopilot.

The 767, 757 had a lot of wing clearance so now the plane could be landed in a slip. The 767, 757 fly the ILS in a crab to around 500 feet above the runway, then the rudder aligns the plane to the runway and drops the wing to slip to a landing, just as a pilot would do. These planes do it so well that landing limits are reduced to 100 meters (300 RVR) with just an alert height instead of a decision altitude. During my first CAT-IIIB landing in the plane after checking out in the 767-200, we were landing in Vienna with thick ice fog. The RVR was 150 meters. As the plane made the approach you would monitor all the instruments and watch it go into align and adjust power. At 100 feet to go (AH) we saw nothing. Then around 40 feet the nose started to come up and the power came back - still nothing out the window! We knew we were on the ground when the auto-spoilers activated and the nose touched the runway. Then, and only then could I see the center line lights of the runway slipping by. The only reason you needed 100 meters visibility was to be able to taxi. And with the help of ASDI (airport surface detection indicator) radar, the ground controller could help you find the gate.

Lou

Mark,

The plane did such a good job of the autoland it was very assuring indeed.

Even in a strong crosswind the autopilot would slip that baby to a pretty smooth landing. The auto-spoilers were set up to deploy at a slower rate during a slip to a landing since only one set of trucks would be compressed at a time. If the wind was from the left, you would have the left wing down enough to counter the wind and the rudder would keep the nose down the runway. Since that was the way you touched down, the spoilers would deploy at the slower rate so the pilot could continue the slip until the wheels were providing enough friction to counter the drift.

The 3 autopilots did such a good job. They didn't get scared, they just did the job! 

Lou

that's some good info Lou!   AND you had to go ahead and mention the L1011 of which there is no good fltsim software out there


Jeff

The L-1011 was a great plane!

Boeing owned the patent on the "S" duct from the 727. Lockheed was willing to pay for the use of the curved duct. What they ended up with is a very stable CAT-III aircraft that was very state-of-the-art! Douglass tried to make a cheap copy of the L-1011 and did not want to pay the royalties to Boeing for the duct. They mounted the center engine high up in the middle of the tail which made the airplane pitch unstable during a go-around. The plane was not certified for CAT-III because of that.

The other problem as became known, was the routing of control cables and hydraulic lines in such a way that there was no redundancy if something bad happened - like the left engine breaking off on takeoff at KORD and taking all the hydraulics with it, or the rear cargo door blowing off during climb and the control cables routed all in one place so when the floor collapsed because of the pressure difference flight controls were lost. Or how about Sioux City.

The DC-10 & MD-11 were nick named "The Death Star."